Vehicle mountable arm for valve operating machine

ABSTRACT

A valve operating device includes a mounting for attachment to a vehicle and an elongate arm, the free end of which is only moveable across the underlying ground. The joints of the arm pivot around vertical axes and the arm is locked into a desired orientation by a brake at each joint. A valve turning machine is at the free end of the arm. The brakes are engaged and released by a control on the valve turning machine.

RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 14/717,231, filed May 20, 2015, which is a continuation of Ser.No. 13/607,423, filed Sep. 7, 2012, now U.S. Pat. No. 9,038,667, issuedMay 26, 2015, which is a continuation of U.S. patent application Ser.No. 13/212,499, filed Aug. 18, 2011, now U.S. Pat. No. 8,387,664, issuedMar. 5, 2013, which is a continuation of U.S. patent application Ser.No. 12/111,423, filed Apr. 29, 2008, now U.S. Pat. No. 8,025,078, issuedSep. 27, 2011, the contents of all of which are incorporated byreference herein in their entirety. The present invention relates tovalve operating machines and in particular to an adjustable armattachable to a vehicle for supporting a valve operating machine whileit is exercising a valve.

BACKGROUND OF THE INVENTION

Municipalities and the like have extensive networks of piping to controlthe flow of water from storage and pumping stations to users. Thenetwork of piping includes numerous valves such that portions of thenetwork can be closed off as needed for service while the remainder ofthe network remains in operation. The piping required for such networkscan range in size from as small as three or four inches in diameter toas large as three feet in diameter. Also, the valves of the systemtypically remain in an open condition or in a closed condition for verylong periods of time. The valves of a municipal water system are locatedbelow ground with an access shaft extending from the valve stem to thesurface through which an elongate key is extended to turn the stem. Suchvalves typically include a screw that is rotatable through one hundredturns or more to fully open or fully close the valve. Also, undergroundvalves undergo a certain degree of deterioration over time and it iscommon for valves to become frozen or locked into their current positionas a result of contamination on the surface of the screw ordeterioration of the parts. As a result, the large amount of torqueneeded to open and close such valves is provided by a motorized valveoperating machine. Such machines are heavy and awkward and when operatedapply a great amount of torque to the key that extends down a shaft tothe valve stem for rotating the valve. Accordingly, to aid in theoperation of such valve turning machines it is common to mount suchvalve turning machines on an arm attached to a truck.

One such mounting device shown in U.S. Pat. No. 6,009,905 to Arnemann isto mount the valve turning machine on a horizontal slide that allows themachine to move horizontally from a first position over the truck bed toa second position spaced from the side of the truck. Such slideablemounting provides rigid support to the valve turning machine while itexercises a valve.

The longitudinally slideable structure, however, has limited mobilitywith respect to the vehicle. Where valves are positioned between variousobstacles such as buildings, curbs, boulders, trees and the like, it maynot be possible for the truck to reach a position where the valveoperating machine may be positioned directly over the shaft leading tothe valve.

Efforts have been made to attach a valve operating machine to amanipulating arm connected to a truck. One such device is sold under thetrademark SPIN DOCTOR by Hurco Technologies, Inc. and disclosed inHurley, U.S. Pat. No. 7,334,606 B1. The Hurley device includes amulti-hinged arm configured as a backhoe with the inner end of the armconnected to a vehicle and the outer end to a valve turning machine. Thearm is pivotable about a horizontal axis generally giving the device ahundred and eighty degree range of rotation with the hinged elbow of thebackhoe arm permitting the free end of the arm to move eight to twelvefeet radially outward of the vehicle. The hinged elbow includes one ormore spring loaded compensating structures to apply a vertically upwardforce to the free end of the arm to compensate for the weight of thevalve turning machine. By virtue of the spring loaded compensatingdevices, the free end of the arm can be manipulated to a positiondirectly over an otherwise difficult to reach shaft to a valve.

It has been found that a valve turning machine mounted on the Hurco armis attached by a key to a valve and with torque applied to the key bythe machine, the machine will shake and toss violently as the valve isexercised. The shaking and tossing is a result of the uneven torqueapplied to the key as the turning screw encounters areas ofcontamination by foreign materials and deterioration of the movingparts. The shaking and tossing of the machine includes verticalcomponents of force which cause the key to be pulled free of the valvestem thereby interrupting the valve turning operation and perhapscausing damage to either the machine or the valve. To retain the machineand the key in their desired orientation with respect to the valve stem,the operator is required to grasp the machine with his arms and use hisbody weight to hold the machine in the desired orientation as the valveis exercised. Since the shaking and tossing of the machine is caused bycontamination and deterioration below ground and not visible to theoperator, the movement of the machine is unpredictable and can alsocause injury to the operator. Accordingly, there is a need for providingan extendible arm for supporting a valve operating machine over a valvestem positioned remotely from a vehicle that will retain the machineagainst all the forces applied to the end of the arm as a consequence offrequent and sudden changes in torque applied to the valve.

SUMMARY OF THE INVENTION

Briefly, the present invention is embodied in a valve operating devicethat has a mounting attachable to a vehicle and an arm having a firstend pivotally attached to the mounting and a valve operating machinerigidly attached to the second end of the arm. The pivot at the firstend of the arm permits rotation of the arm only about a vertical axissuch that the free end of the arm is moveable through a plane parallelto the underlying ground below the vehicle to which the mounting isattached. The arm is made with sufficient strength and rigidity that thefree end will provide support to the valve operating machine at thesecond end against the vertical forces applied by gravity and resultingfrom torque applied by the valve operating machine to turn a valve stem.

The arm includes a lock for selectively locking and unlocking the pivotbetween the mounting member and the first end of the arm. In thepreferred embodiment, the lock is in the form of a hydraulicallyoperating disc brake. The lock includes a control for selectivelyengaging and disengaging the lock, and the control is operated from alocation at the second end of the arm. Accordingly, an operator can usehis hand to grasp a handle at the second end of the arm and use thethumb of that hand to operate the control to disengage the lock. Theoperator can then manually manipulate the second end of the arm untilthe valve operating machine is over a shaft leading to a valve stem.Once the machine is properly positioned, the operator can release thethumb operated control to engage the lock thereby retaining the arm in arigid position over the shaft to the valve.

In another embodiment of the device, a second arm is provided betweenthe second end of the first arm and the valve operating machine. In thisembodiment, a second pivot is provided between the second end of thefirst arm and the first end of the second arm with the second pivot alsorotatable only about a vertical axis such that the free end of thesecond arm is also moveable through a plane parallel to the underlyingground. The second arm is also made with sufficient strength andrigidity such that the second end of the second arm will retain thevalve turning machine against the forces of gravity and the forcesgenerated from the machine when it applies torque to the valve stem.

BRIEF DESCRIPTION OF THE DRAWINGS

A better and more complete understanding of the invention will be hadafter a reading of the following detailed description taken inconjunction with the drawings wherein:

FIG. 1 is a side elevational view of a valve turning machine mounted ona vehicle in accordance with the present invention;

FIG. 2 is an enlarged isometric view of the arm and valve operatingmachine mounted on the truck shown in FIG. 1;

FIG. 3 is a further enlarged fragmentary isomeric view of the arm shownin FIG. 2 depicting the arm mounting and the first pivot thereof;

FIG. 4 is a fragmentary cross-sectional view of the arm shown in FIG. 2showing the inner parts of the two pivots;

FIG. 5 is an isometric view of the second end of the second arm showingthe valve operating machine and its controls;

FIG. 5A is an elevational view of an electronic controller; and

FIG. 6 is a schematic drawing of the hydraulics for operating the armshown in FIG. 2.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring to FIGS. 1, 2, 5, and 6, a vehicle 10 is fitted with anelongate valve operating device 12. The valve operating device 12 has amounting portion 14 and an arm. The arm consists of a first arm portion16 having a first end 18 pivotally attached to the mounting portion 14by a first pivot 20 and a second end 22 attached by a second pivot 24 toa first end of the first section 26 of a second arm portion. The secondarm is telescopically extendible and therefore the first section 26thereof is a generally hollow tubular member with a rectangularcross-section, the first end of which is attached to the second pivot 24and the second end of which telescopically receives the first end of asecond section 30. The second section 30 has a generally rectangularcross-section with outer dimensions a little smaller than the innerdimensions of the first section 26 such that the second section 30 willnot rotate axially with respect to the first section 26. Rigidlyattached to the distal end of the second section 30 is a valve turningmachine 32. An adjustable screw 33 with an enlarged head 35 in the shapeof a handle is threaded into a complementarily threaded hole, notnumbered, in the wall of the first end section 26 and against thesurface of the second section 30. When the screw 33 is tightened againstthe second section 30, the first and second sections 26, 30 arelongitudinally locked to one another and when the screw 33 is loosened,the second section 30 is longitudinally moveable with respect to thefirst section 26.

The valve turning machine 32 includes a hydraulic motor 34 and anelectronic controller 36 which may be detachable from the body of themachine 32 but communicate with the machine either through a wire, notshown, or by wireless technology. The controller 36 includes amicroprocessor having a memory for storing information about the valve37 to be controlled such as the rotational direction for opening thevalve 37, the number of turns to move the valve from fully closed tofully open position, the maximum torque that can be applied to the stem,the current position, open or closed, of the valve, and the date onwhich it was last exercised. Using information in the memory plus inputfrom an operator, the controller operates a sequence of valves 33, 35 ina manifold 38 to direct hydraulic fluid from a pump 40 (shown onlyschematically in FIG. 6) through a plurality of hoses 41, 43 (also shownonly in FIG. 6) to operate the motor 34 in either a clockwise orcounterclockwise direction. The motor 34 drives a rectangular sleeve 42on the machine 32 into which is inserted an elongate key 44, the lowerend of which fits over a polygon shaped stem, not shown, of a valve forrotating the valve. The valve turning machine 32 is the type known inthe art and such a machine is described in further detail in U.S. Pat.No. 5,381,996, which is incorporated herein by reference.

Referring to FIGS. 2, 3, 4, and 6, the mounting portion 14 includes amounting plate 46 with a plurality of mounting holes 47 therein forattachment to a stable part of a vehicle 10, such as the truck bed 48,which remains generally parallel to the level of the underlying ground50. The mounting portion 14 also includes a pedestal 52 extendingvertically from the mounting plate 46, the upper end of which defines avertical axis around which the first pivot 20 rotates. The first pivot20 includes a pair of bearings 54, 56, the inner races of which arefitted tightly around the upper end of the pedestal 46 and the outerraces of which are rigidly retained in tubular mounting cup 57 at thefirst end 18 of the first arm. The second end of the first arm portion16 will therefore rotate through a plane that is perpendicular to thepedestal 52 and parallel to the bed 48 of the vehicle 10 and parallel tothe underlying ground 50.

Positioned below the bearing assemblies 54, 56 and surrounding a centralportion of the pedestal 52 is a generally planar horizontal first brakedisc 58. Attached to the first end 18 of the first arm portion 16 by apair of brackets 53, 55, each of which has a pair of downwardlyextending slide pins 61-61 attached thereto, is a first pair ofhydraulically operated brake calipers 60, 62 that float with respect tothe brake disc 58 on slide pins 61-61. Each of the brake calipers 60, 62includes first and second parallel operated pistons, 66, 67, 68, 69,moveable within piston housings, portions of two of which, numbered 63,64, are visible in FIG. 3. The pistons are connected by rods, notvisible, to a pair of upper pads, also not visible, that rest on theupper surface of the brake disc 58. The calipers 60, 62 also support apair of lower pads positioned against the lower surface of brake disc58. Portions of two of the lower pads, numbered 70, 72 can be seen inFIG. 3. Upon operation of the calipers 60, 62, the pistons 66-69 in thehousing 63, 64 are extended thereby pressing the upper pads against theupper surface of the brake disc 58 and simultaneously drawing the lowerpads 70, 72 against the lower surface thereof to lock the first armportion 16 in a fixed orientation with respect to the mounting portion14 and the vehicle 10.

Extending vertically upward from the first end 26 of the second armportion 26, 30 and perpendicular to the length of the second arm portion26, 30 is a second pedestal 74, the upper end of which serves as theaxis of rotation for the second pivot 24. The inner races of a secondpair of bearings 76, 77 is fitted around the second pedestal 74 and theouter race is received within a tubular mounting cup 78 welded to thesecond end 22 of the first arm portion 16. The mounting cup 78 retainsthe axis of rotation of the second bearing 76, 77 around the secondpedestal 74 parallel to the axis of rotation of the first set ofbearings 54, 56 around the first pedestal 52. Accordingly, the secondarm portion 26, 30 will rotate about an axis defined by the secondpedestal 74 with the length thereof parallel to the bed 48 such thatwith the outer end thereof moving in a plane parallel to the bed 48 ofthe vehicle 10 and parallel to the underlying ground 50. It should beappreciated that the distal end of the second end always moves withinthe same plane regardless of whether the movement occurs as a result ofrotation of the first pivot 20, the second pivot 24, or the longitudinalextension or retraction of the second arm portion 26, 30 bytelescopically sliding the outer portion 30 into or out of the firstportion 26. Fitted around the circumference of the second pedestal 74 isa second brake disc 80 and attached to the first end of the second armportion 26 is a second pair of calipers 82.

Extending downwardly from a second pair of brackets welded to the secondend 22 of the first arm portion 16 (one bracket 79 is visible in FIG. 2)are a pair of slide pins 81-81. Slideably mounted on each pair of slidepins 81-81, so as to float above the brake disc 80, is a second pair ofcalipers 82, 83. The second pair of calipers 82, 83 are structurallyidentical to the first pair of calipers 60, 62 and each encloses a pairof pistons 84, 85, 86, 87 with each piston connected by a rod to anupper pad positioned against the upper surface of the second disc brake80. The second calipers 82, 83 also include first and second lower padspositioned to be compressed against the lower surface of the secondbrake disc 80, one opposite each of the upper pads. Upon actuation ofthe second pair of calipers 82, 83 the pistons 84-87 will compress theupper pads against the upper surface of the disc brake 80 and draw thelower pads against the lower surface thereby locking the second armportion 26, 30 in a fixed orientation with respect to the first armportion 16.

The two sets of bearings 54, 56 and 76, 77 ensure that the distal end ofthe second arm portion 30 is only moveable within a plane parallel tothe underlying ground 50, and allow the arm to be manipulated by anoperator using only one hand while the two brake assemblies 58, 80 aredisengaged.

Referring to FIGS. 5 and 6, the pistons 66-69, 84-87 of the first andsecond pairs of calipers 60, 61, 82, 83 are all hydraulically operatedby the application of hydraulic fluid from the pump 40 through ahydraulic supply line 96 connected to a control valve 98. A releasevalve 100 retains or releases hydraulic pressure from the pistons. Whenthe control valve 98 is opened, hydraulic pressure generated by the pump40 will actuate the pistons 66-69, 84-87 in both calipers 60, 82 therebylocking the first arm 16 in a fixed orientation with the vehicle 10 andthe underlying ground 50 and locking the second arm portion 26, 30 in afixed orientation with respect to the first arm portion 16. When thepressure is released by the release valve 100, the pads of the calipers60, 61, 82, 83 will relax and the first arm portion 16 will be free torotate about the first pedestal 52 and the second arm portion will befree to rotate about the second pedestal 74.

An important feature of the invention is the provision of a handle 102positioned at the outer end of the valve turning machine 32 where it iseasily grasped by an operator. At the distal end of the handle 102 is acontrol button 104 for a valve control 105. When the button 104 on thehandle 102 is depressed, the valve control 105 operates the valve 98 andthe release valve 100 to release hydraulic pressure from the two sets ofcalipers 68, 82 thereby releasing the brakes. Conversely, when thebutton 104 is not depressed, the control valve 98 and release valve 100are configured to apply hydraulic pressure to the calipers 60, 61, 82,83 to thereby lock the first and second arm portions 16, 26 in theirdesired orientation.

Although the control button 104 is described as being at the end of thehandle 102, it should be appreciated that the intent is to have theactuation device located where it is convenient to the operator as hemanipulates the arms 16, 26, 30. It is therefore within the spirit ofthe invention to provide an actuator 106 for operating the control 105on the electronic control 36. The device 106 may be in addition to thebutton 104 on the handle 102, or in substitution therefore.

Another important feature of the invention is that the mounting portion14, the first and second arm portion 16, 26, and the first and secondpivots 20, 24 are all made with sufficient strength and rigidity to holdthe valve turning machine 32 within a plane of movement defined by thesecond arm portion 26. Specifically, the elongate parts are madesufficiently strong and the bearings of the pivots are sufficientlylarge and rigid enough to hold the valve turning machine 32 at a fixedelevation in opposition to the forces of gravity applied by virtue ofthe weight of the valve operating machine 32 and in opposition to thevertical forces incurred as the machine 32 applies torque to a valvestem. Accordingly, an operator will not be required to use his own bodyto retain the machine 32 against the forces that shake and throw themachine when torque is applied to a valve.

An operator using a truck 10 fitted with a valve operating device 12 inaccordance with the present invention, will drive the vehicle 10 to aposition near an underlying valve 37. Once the vehicle 10 is properlypositioned, the operator can grasp the handle 102 with one hand,compress the button 104 with the thumb of that hand, and using the samehand manipulate the distal end of the second arm portion 26 until it ispositioned immediately above the valve 37 to be exercised.

When the arm is properly positioned above a valve stem, the operator canrelease his grip on the button 104 thereby causing the control valve 98and release valve 100 to allow hydraulic pressure to be applied to thecalipers 60, 61, 82, 83 and lock the first and second arm portions 16,26, 30 in their present orientation. With the arms so locked, theoperator can position the key 44 in the sleeve 42 of the valve turningmachine 32 with distal end thereof fitted over the stem of the valve.Once the key 44 is attached to the valve the operator can then use thehand held electronic controller 36 to operate the valve turning machine32 to exercise the underlying valve without requiring the operator totouch the machine 32 while it is operating. The operator, therefore,does not have to use his body weight to retain the machine 32 againstthe forces generated as torque is applied to the valve as is the casewith machines mounted on prior art manipulating arms.

After the valve has been fully exercised, the operator can remove thekey 44 from the valve stem and the sleeve 42 thereby disconnecting thevalve operating machine from the valve. The operator can then againgrasp the handle 102 and depress the button 104 causing the controlvalve 98 and release valve 100 to release hydraulic pressure to thecalipers 60, 82 and allow the operator to easily manipulate the arm 12and fold it against the side of the vehicle 10 for transporting toanother site.

While the present invention has been described with respect to a singleembodiment, it will be appreciated that many modifications andvariations may be made without departing from the spirit and scope ofthe invention. It is therefore the intent of the appended claims tocover all such modifications and variations that fall within the spiritand scope of the invention.

What is claimed:
 1. A valve operating device comprising: a mounting; afirst pedestal extending vertically from the mounting, wherein the firstpedestal defines a first vertical pivot axis; a first arm having a firstend and a second end, wherein the first arm is pivotally coupled to thefirst pedestal at the first end of the first arm, and wherein the firstarm is configured to rotate about the first vertical pivot axis in asubstantially horizontal plane that is generally perpendicular to thefirst pedestal; a first disc brake coupled to the first end of the firstarm to selectively prevent rotation of the first arm relative to themounting, wherein the first disc brake includes a first disc and a firstpad configured to engage the first disc to prevent rotation of the firstarm relative to the mounting; a second pedestal defining a secondvertical pivot axis and positioned at the second end of the first arm; asecond arm having a first end and a second end, wherein the second armis pivotally coupled to the second pedestal at the first end of thesecond arm, and wherein the second arm is configured to rotate about thesecond vertical axis; a second disc brake coupled to the first end ofthe second arm to selectively prevent rotation of the second armrelative to the first arm, wherein the second disc brake includes asecond disc and a second pad configured to engage the second disc toprevent rotation of the second arm relative to the first arm; a valveturning machine coupled to the second end of the second arm, wherein thevalve turning machine includes a motor, a handle and a controlconfigured to operate at least one of the first disc brake and thesecond disc brake; and a first bearing coupled to the first pedestal,wherein the first bearing includes an inner race and an outer race,wherein the inner race is tightly fitted around the first pedestal andthe outer race is rigidly retained at the first end of the first arm. 2.The valve operating device of claim 1, wherein the first arm and thesecond arm are hollow and tubular along at least a portion thereof. 3.The valve operating device of claim 2, wherein the first arm and thesecond arm are rectangular in cross-section.
 4. The valve operatingdevice of claim 1, wherein the motor of the valve turning machine is ahydraulic motor.
 5. The valve operating device of claim 1, furthercomprising an electronic controller detachable from the valve turningmachine and in communication with the valve turning machine.
 6. Thevalve operating device of claim 5, wherein the electronic controller isin communication with the valve turning machine through a wire.
 7. Thevalve operating device of claim 5, wherein the electronic controller isin wireless communication with the valve turning machine.
 8. The valveoperating device of claim 5, wherein the electronic controller includesa microprocessor and memory, wherein the memory is configured to storeinformation pertaining to operation of the valve operating device. 9.The valve operating device of claim 1, further comprising a hydraulicpump, a manifold, and at least one valve in the manifold to directhydraulic fluid from the pump through at least one hose to operate themotor.
 10. The valve operating device of claim 1, further comprising asecond bearing coupled to the second pedestal, wherein the secondbearing includes an inner race and an outer race, wherein the inner raceof the second bearing is tightly fitted around the second pedestal andthe outer race is rigidly retained near the second end of the first arm.11. The valve operating device of claim 10, further comprising a thirdbearing and a fourth bearing, wherein the third bearing is coupled tothe first pedestal and the fourth bearing is coupled to the secondpedestal.
 12. The valve operating device of claim 11, wherein each ofthe first and third bearings includes an inner race tightly fittedaround the first pedestal and an outer race rigidly retained at thefirst end of the first arm.
 13. The valve operating device of claim 12,wherein each of the second and fourth bearings includes an inner racetightly fitted around the second pedestal and an outer race rigidlyretained at the second end of the first arm.
 14. The valve operatingdevice of claim 1, wherein the handle is positioned at an outer end ofthe valve turning machine.
 15. A valve operating device comprising: amounting; a first pedestal extending vertically from the mounting,wherein the first pedestal defines a first vertical pivot axis; a firstarm having a first end and a second end, wherein the first arm ispivotally coupled to the first pedestal at the first end of the firstarm, and wherein the first arm is configured to rotate about the firstvertical pivot axis in a substantially horizontal plane that isgenerally perpendicular to the first pedestal; a first disc brakecoupled to the first end of the first arm to selectively preventrotation of the first arm relative to the mounting, wherein the firstdisc brake includes a first disc and a first pad configured to engagethe first disc to prevent rotation of the first arm relative to themounting; a second pedestal defining a second vertical pivot axis andpositioned at the second end of the first arm; a second arm having afirst end and a second end, wherein the second arm is pivotally coupledto the second pedestal at the first end of the second arm, and whereinthe second arm is configured to rotate about the second vertical axis; asecond disc brake coupled to the first end of the second arm toselectively prevent rotation of the second arm relative to the firstarm, wherein the second disc brake includes a second disc and a secondpad configured to engage the second disc to prevent rotation of thesecond arm relative to the first arm; and a valve turning machinecoupled to the second end of the second arm, wherein the valve turningmachine includes a motor, a handle and a control configured to operateat least one of the first disc brake and the second disc brake; whereinthe first disc brake further includes a first caliper; wherein the firstcaliper is one of a pair of hydraulically operated first calipers of thefirst disc brake, wherein the pair of first calipers are moveablerelative to the first disc on a pair of pins, and wherein each of thepair of first calipers includes a pair of parallel pistons moveablewithin piston housings, and wherein the pad is one of a pair of firstpads coupled to the pistons, and wherein operation of the pair of firstcalipers is configured to press the pair of first pads against the firstdisc to prevent rotation of the first arm relative to the mounting. 16.The valve operating device of claim 15, wherein the pair of first padsis an upper pair of first pads, wherein the first disc brake furthercomprises a lower pair of first pads, and wherein operation of the pairof first calipers is configured to press the upper pair of first padsagainst an upper surface of the first disc and simultaneously press thelower pair of first pads against a lower surface of the first disc. 17.The valve operating device of claim 16, wherein the second disc brakefurther includes a second caliper.
 18. The valve operating device ofclaim 17, wherein the second caliper is one of a pair of hydraulicallyoperated second calipers of the second disc brake, wherein the pair ofsecond calipers are moveable relative to the second disc on a pair ofpins, and wherein each of the pair of second calipers includes a pair ofparallel pistons moveable within piston housings, and wherein the secondpad is one of a pair of second pads coupled to the pistons, and whereinoperation of the pair of second calipers is configured to press the pairof second pads against the second disc to prevent rotation of the secondarm relative to the first arm.
 19. The valve operating device of claim18, wherein the pair of second pads is an upper pair of second pads,wherein the second disc brake further comprises a lower pair of secondpads, and wherein operation of the pair of second calipers is configuredto press the upper pair of second pads against an upper surface of thesecond disc and simultaneously press the lower pair of second padsagainst a lower surface of the second disc.
 20. The valve operatingdevice of claim 15, wherein the handle is positioned at an outer end ofthe valve turning machine.